Multiple drop-hoist system of circuits.



"A. M. BOYLE; MULTIPLBDROPHOIST SYSTEM ,0? CIRCUITS.

APPLICATION FILED JULY 20 19.074

Patented July 26, 1910 ZSHBETC-BKEET 1 M TJM WM A.;M. GOYLE'. MULTIPLE DROP HOI SI" SYSTEM OF CIRCUITS.

965,442. mum! Hm Patented July 26, 1910.

QIHEETS-BHBBT 2.

\mm mun R WITNESSES INVENTOR WW I Mme/v5) To all whom it may concern:

ANDREW M. COYLE, OF NEW YORK, N. Y.,

OFFICE.

ASSIGNOR TO OTIS ELEVATOR COMPANY,

OF JERSEY CITY, NEW'J ERSEY, A CO RPORATION OF NEW JERSEY.

MULTIPLE DROP-HOIST SYSTEM OF CIRCUITS.

965,442. v Application filed July 29,

Be it known that (,Annnnw M. Corps, a' citizen of the Uiiitcd States, residing in New York, in the county of New'York and State of New, York, have invented a new and useful Improvement in Multiple Drop-Hoist Systems of Circuits, of which the following is a specification. L

My invention relates to an improved system of push button motor control, and has for one of its objects the provis on of means for selecting orcontrolling a plurality of hoisting machines by pushbuttons or switches, the speed at which same shall be I is. acting as a operated being operated switch. D 0

A further object of the invention is to regulate the speed of the l10ltl'i. mechanism while lowering by int1'odujcii'.g-...1ore or less resistance in shunt to' the armature circiiit, and thereby utilizing the dynamic braking action of the motor when the same generator due to the unbalanced descending load. 7 Other objects willippear hereinafter. The accompanyingfdrawings illustrate my invention as applied to a multiple curtain determined by a manually hoist and while the same is particularly adapted to a hoisting mechanism of this.

I Generally speaking,

character, it is equally well adapted to hoisting machines of all kinds in which an elec j trlc motor is usedfor hoisting and lowering:

a multiple curtai'n hoist -belongs' to that class of hoisting machines I ,ferred form wires-2 and and in which a single motor operates through friction mechanism a number 'of-hoi'sting drums, each of which controls a drop curtain such as is used in theaters, etc.

Referring how to the drawings, Figure l is a diagrammatic view, showing the preof my invention, and Fig. 2 is a similar view of :1 modification.

Fig. 1 .will first he described. In this form, a main line switch 1 serves to the source of electrical supply to the feed 3, respectively, designated by D and l are the motor reversing switches, and since they are similar in construction a description of one applies equally well to the other. The switch D comprises asolcnold and a plunger 4 movable therein, a motor armature reversing switclnand an auxiliary switch. To the plunger 4 is con- Specification of Letters Patent.

connect Batented July 26, 19-10. 1907. Serial No. 386,089.

nected arod 9 carrying a contact plate 6 and an insulating ban14. "The latter carries two contacts 12 and '13 whichare in line with and arranged to engage two stationary contacts 10. and 11, respectively. The contact plate 6 bridges two fixed contacts 7 and 8 when the electro-magnet is deenergized.

When energized, however, the plunger 4 is lifted, carrying with it the rod 9, contact plate 6 and the insulating'bar 14.

25 designates the'motor armature, which may be connected to curtain hoisting apparatus as illustrated in..my copending application, Serial No. 282,234, filed October 11, 1905, for an improvement in multiple hoisting apparatusesf It: should be understood -however, that the present system of con: trolling apparatus for electric motors may be applied to hoisting machinery other than that for hoisting curtains, for example, furnace hoists, where a load is lifted and the empty car then 'permitted ing the motor forward. y

30 designates the shunt field winding.

50, 51 and 52 designate sections of a resistance which are controlled by the switches operated by the magnets 41, 42 and 43.

31 designates a slow-down switch shown. in the drawing diagrammatically as comprising a contactanalgcr or -plate which normally bridges two fixed contacts 32.

a plunger 34. To the latter is connected a rod 71 which in turn isconnected to, but isolated from, three contact plates 35, 36 and 37. The plates 35 and 236 normally rest on the contacts 37, 38 and39, 40, respectively. When the solenoid 33 receives current to lift its plunger 34,1;he plate '37 will electrically (52, 63 and 64'de'signate the starting res stances, and 53, 54 and 55 are magnets for The sta tionary contacts 7 and 8 will then be elec-" to descend, drivand 11, f

rod 17,

33 designates a magnet solenoid in 'which is movable connect the contacts 40, 40.

the 'rposeyof actuating brake'apparat-us 51] ning of :the hoisting apparatus.- '1' have s tbb'e lifted when t be curtain approaches a res-istoperating switches to control ances. r

' 7 1 ancl76 d'esig'nate"manual switches. f v

100 designates an operating or speed'con- E trolling switch which comprises a rheostat arm 102 pivoted at 105, which 1s arranged to make contact with fixed segmental conductors or-contact strips 106, etc. Directly' under this switch in Fig. 1 are .shown dia 10 grammatically a series of up push but tons and a series of down push buttons; These push button switches are self-hold ng in that when a button is pushed a circuit is completed through a magnetforming; a

part 0' the push button-deviceqand operat- I, mgito hold the button-in against the faction of a sprin'gzor equivalentdevice, the parts remaining in this position until the mag net is denergized, whereuponthe'buttona'sssimes its original position automatically, These push button switch devices--i1re alike in construction and may be-constructed 'in many specifically diiferentwa In th s instance oneofthe terminals 0 each of'the hrakemagnets' is connected through an automatic st'op motion switch to the. solenoids 115 and 131, and thence tothe core 116 of th'cpush'hutto'n'electrormagnct. h j, The 'brake magnets are designated- "by the 80 numbers 122 to 127, inclusive, and are for said t'o Te ease the same and ermit the hoisting apparatus to be con'necte' to the electric motor. 'VVhent-hebrake magnet is deiiner- 85 gizedthe brake will at once he applied by k a lira-kc .sprin :andthe' hoisting'mechanism disconnected .i'om-the electric motor. The brake a-p aratus, however, may be of the usual we 1- knc'iwn type f in connection with 4 0 ordinary hoisting apparatus. I prefer,

" \however, when applying my im 'rovedconti'olling'apperatus as herein-disc osed to curtainhoisting apperatnspto use-'- the brake a paratus illustrated in my co-pending ap picntion-hereinbefore referred to. I. r

M It should be understdod'thateach unit vofthe multiplehoistingggperatus'is provided with stop motion m anism'- for the f-puiriose of flreventing any-possible overd'unherein 1 shown-dial gimmnmticallyf the switches of'bl'ie stopmction mechanism,--suclr switches comprisiglg' fixed contacts 119, 120 and 121-; and mov lei contact plates 1-17ahd 118, one-f limit of travel and th'e other to be lifted when-the curtain ap rcachcsits lower limitof travel to sac-a t e" dcehergiz'ation o0 consequent stoppingnof-v the corresponding. unit of the multiple. hoisting, apparatus.

ZUhe-dinection-of rotation of the motor is contbollecl -by the reversing switches I D and H The a ccelertiticn 0f the match when-:opa tureand 'by'c-changing the field strength, In

lowering the curtain a fixed resistance is in- .cluded n thegarmature circu1t whilea var1- 1 able resistance is placed iii-shunt thereto, the

sfrcngtl 'of the field being also varied. The P heav'y. lines in the accompanying {drawings denote the main or motor circuits-gwhile the lighter lines denote the shunt field and opcrating circuits I p I I -Assumingthat themain line two-pole switch 1 is closed and that thepositive and negative mains are connected to a sourceof 30 :current supply having proper. potential for the operation'of the motor, the leads 2 and 3 system in a position ofinaction or rest. In order. to trace the various circuits, it will be inecessaryto operateone'of the selected push buttons, such as 113. If at this time the 'aarm 102 is in the osition shown a circuit iwill be completed from the positiqe lead 2 by wire 139,1 switch 72, conductor 137, switch 0 73, conductor 136, the three relay magnets 78, '69 and 80, conductor 135, connecting bar 111, contact 114, core 116, winding .lli e- :cluctor- 134;, contacts 119, 120 and bridge piece ll'i briike magnet 122 and" conductor 133 to the ,negative lead 3. This circuit g froin the-positive main to the-negative main includes the relay magnets 78, 79 and 80,- the 'push button magnet at'the extreme left, and the brake ma net 122. The brake mechanism 'willlnow e released by the'magnet i122 .and the magnet .core' 116 willhold the contact Hat-in circuit-closing position, as an armature, since said contact 114 is composed of magnetic material such as soft iron. 5

Substantially at the same time the magnets .78, 79 and 80'will close the switches 90, 91

iand 92. The switch 90 controls a circuit to the magnet of the reversing switch Ur Therefore when the switch 90 is jclosed a circuit may be traced-from the positive lead= 2 through the conductors 139'," 143, switch 90, conductor 141, solenoid of the reversing" switch U, contacts 8, 7 andbridge' piece and thence by conductor 84 to theJnegative, '5 lead 3.' 'It "shouldbe noted that when the plunger 5 are separated sothat the circuit of the solenoidof the-reversing switch D cannot possibly be excited-with current so long as the d reversing switclt'U 'is in closed position."

The'switch U havingoperated, theniotor now receives current,- the circuit being as follows? from. the conductor '2 'tosuand .throughcontacts19,-21, brush 24, armature 1 5 25,-brush- 27,.conductcr 26, contacts 22, 20, icondu'ctor 164., starting resistances 62, 63, 64,

and'thence to the negative lead 3. 1 I

'The'shunt field Winding. 30 isconnectcd 65 crafting-the hoisting apparatus, to'l'ift aficur-- by'coud'uctors 163,0ontacts39, 40- and plate v will be ,alive. The drawing shpws the is'liftedthe contactsI16 and 18" I m 36, and conductors130, 129 across the leads 2 and 3. The motor may now startyand -acslstance 96. Them'agnets 53, 54 and 55 are accelerating electro-magnets, in that they operate switches to control the resistances 62, 63 and 64. They may,

however, also be termed speed co ntrolling electro-magnets.

These magnets are connected together as a 55 are not energized since all their terminalsslow speed, or wlie .mentl 104, arm 102,

shown. The left-hand terminal of the magnet 53 is connected to the contact by the conductor 152, while the right-hand terminal of magnet is connected by conductor 150 directly to the segmental strip 109.

V hen the arm 102 is in the position shown and the button 113 has been actuated to effeet the operation of the motor to a predetermined slow speed, the magnets 53; 54 and are still connected to isola are the magnets 41, 42 an this time, since ed contacts; nor 43 energized at no circuit for current flow through them is provided. It should be noted that at this time the shunt T'field winding 30 not only receives current from the positive lead through the conductor 130, but also from a parallel circuit by way of conswitch 72,.conductor 138, se'gsegnient 103 and conductor 139,

ductor 153.

When the motor attaiiis a predetermined n the a Sufficient counter-electro-motive forcef't he nets 81, 82 and 83 remain strip 112.

solenoid 33 will liftxitscore34 and cause the plates 35'and 36 to be lifted out of engage-' meat with the contacts on, which they are rest1ng, and move the: plate37 into engagement with the contacts 40, 40. The .con-

d uctors 130 and 163being disconnected from .9 each other by. the winding 30 cangreceiveicurrentonly by way of the'switch-IOO ahdkionductor 153. w-isc lifting of-the plunger plate 36, the shunt field "v Other.- 34 and the opcrzu 'tion of the switches connected thereto have no further immediate 'eflect. The relay magthey are open-circuited at t econducting In order to increase the speed of the motor the rheostat arm 102tmust be moved to the right. \Vhen it connects together the .sem mental strips 104, 103 and 107 current will ilouyi'rom the positive-main through wires 1 59, 133, strip 104', arm 102 to contact strip 107 and thence through resistance 96, conmotor has builh gpa inoperative, since ductor 147,

point 148 which is one terminal ofthe mag" net 53 The other terminal of this magnet being connected by conductor 152 to the contact 40, the current wiltcontinue to flow through the latter and the bridge piece 37, and thencethrough conductors 151, 26, contacts22, 20, conductor 164, resistances 62, 63, 64, to the negative lead 3. The magnet 53,

will therefore be connected across the motor armature 25, and if the counter-electm-motive force in the latter is sul'licient the magnet 53 will be energized to cause the plate-56 switch 92, conduct or 146, to the 0 to electrically connect the contacts, 59 and short-circuit the resistance 62 to cause increased potential to be applied to the motor armature. The motor Wl-ll now accelerate to a higher speed. It should'be noted that when the rheostat arm 102 passes from the strip 106 the left-hand terminal of the magnet 41 is entirely isolated. The left-hand terminals of the magnets 42 and 43 are al.- ready isolated.

' By-Inoving the rheostat arm 102 oil the contactstri 107 and onto the contact strip 108 a ,circu1t will be closed for the magnet 54 from the positive lead 2 by way of conductor 139, switch '72, conductor Z138, strip 104, arm 102, strip 108, resistan e 99, conductor 145, switch 91, conductot/144to the point 149, and thence through /the magnet 54, magnet 53, conductop 'l52, the switch comprising the plate 37, t:onductors 151, 26.

contacts 22, 20, conductor 164,- contacts 59 and switch plate 56, resistances 63, 64, to the negative lead '3. The magnetsy53, 54 and resistance 99 are now connected in series with each other across the motor armature and if the counter-electrormotive force of the latter is sufficient the magnet fi l-Twilllzfflifictthe plate 57 to connect the contact 60 ihd'thereby short-circuit the resistance 63. The motor will then run at increasedspeed, due to an increase of potential across its armature brushes. A further movement of the rheostat arm 102 causes it to pass off the strip 108 0nto'the the directconnection through the conductor 150 from the strip 109130 the magnet 55, all three of themagnets 55, 54 and 53 will now. be connected in serieswith each other across the motor armature,;'so that if the speed of the latter is sufficient the magmet 55 will'also be energized to cause. the plate 58 to electrically connect the contacts 61 and thus short-circuit the resistance 64. All the starting resistance having been short-circuited or cut out, the armature is connected directly across the mains and will accelerate to'full speed. v I The resistances 96 and 99 are so proper tioned that the amount ofcurrent furnished ,to'tl 1 magnets 53, 54 and 55 is the same,

whet er one,'tii'o or all three are energized.-

The esistancc 96 is substantially twice strip 10 9. By reason of I i ,fgreat as the winding of one of the magnets;

W is reached: This adjustment may be secured in many-specifically *diilereut ways, but in" this instance,- I have shown-the plun ers 68," (i9 and 70 projecting into the cores iflerent distances so that thema-gnet 53-will beffirstto operate, then- 54, =and-finally 55 even though the switch arm 102 "be immediately thrown intoconnectio'nwith the stri-p 109.

Upon moving the rheostat arm .1021 toits extreme right-hand iposition it wiIlconne'cttogether segmental. strips 10 1, 1'10 an d lfi and u will leave the contact strip-103. "Now the .zsvllatter is connected hv condu'c'tors-153, 129* to the shunt-field winding 30." FThe'refore when the rheostat arm asses ofi the strip 103 the-circuit-of-,the.-s unt field-windingwould open atthet-point were it not for the" fact that the strip 110 which is now ill-818$ trical engagement with the rheostat arm '102,

is honnected through a-resistancelm th the- -strip 103; It=wil1 therefore be seehthatthe: resistance 101" is placed in series W1th 13l18' shunt field'winding 'Thiswill 'cause-zthe field to become weakened and the speedflof the motor to accelerate still further. V

As the load onthe electric1not0r ap preaches its limit of travel the stop motion 40 switch-will be opene'd by the lifting-niche v contactbarll'l out ofenga'gement with the statio nary contacts 119 and 120.' =Thiswill at once 'effectthe stopping of -theihoisting mechanism by reason of the denerfgization 4 5 of-the'brake magnet 122. The three :relay' -ma'gnets,-78, 79 9116180 will also be deiinergigedjbyatheir circuit being opened at the push; button contact 11 1, for whergthe bar 1 17 is lifted current is cut off from the sultan 5 0 'oid 115 and-the armature 114 is therefore released, 'Ihe' deenergizat-ion of the magnets-78, 79- and 80 causes the switches 90, 91

and 92to automatically open; The opening l of the switchQOcauses the ciirrent to be cut oil from the magnet of thereversingswitch l, Land the latter willitherefQI-Q:OPerate automatically to: open position and out off vthe I main current sup y from the motor. It

- should he observe ,howeirefigthat the shunt field windin' glstill receives current through"- "the speedgtxmtrolling switch lilfi and resistance 101 As-soo as the reversing switch ositionythe agnets 53,

' redeenergized, sin their are iconductor 133 to thenegative lead 3.

I at, the contacts as, QQJS-" The resistances 62, 63 alias-4am therefore be reinserted. Asthe motor comes tozrest the potential across its armature will'decrease until the magnet 33 becomes deenergized anddrops its core 34 torestabl ish the normal positions of the switches controlled thereby. "The field-resistance will be shortcirouit cd so'thatthe motor will have maximumifieId-StnenQth when again started. In-

.stead offirshpushing the selected button 113 and fthen bringing the motornp to full speed by moving the, rheostat arm 102 to theright =from'its left-hand position, if desiredithe' switch 100 may be placed in such position as to give the speed required and thena selected push button operated; In such case-the motor would start and acceler' dug in succession to cut out or short-circuit the resistances 62, 63 and 64.,

- In lowering the curtain operation is ate automatically to the desired speed, the magnets 53, 54 and 55 automatically operatsomewhat different. To explain this, let it be assumed that the switch arm 102 is in the position shown; in Fig. 1. Then if a downlpush-button, such as that desig nated 128 for example, is actuated a circuit ,givq-coil 131, conductor 134", stop motion tch, brake magnet122, and thence by the brake apparatus will be released and the pushbutton 1,28 held inby its magnet and,

the-relay magnets 81, 82 and sa'wi'u be energized to close their respective switches 98,

94: and 95. The switch '93 'controls the electro-ma%'net of thereversing switch D, and

when 0 used forms a circuit for such magnet The from-the positive lead 2 b conductors 139,

1-57, 112 to a:nd through tiemagnet of reverslng switch '1), and thence through the auxiliary switch of the reversing switch U10 the negative lead- 3. The magnet of the reversing sWitchD is now in a circuit acrossthe mains and the contacts 12 and 13 are brought into engagement-with. thefixed contacts 10 and 11, respectively, and the contacts 7 and 8 are electrically dis; connected to prevent any possible circuit throughth'e magnet of the reversing switch U. Upon the closing of the reversing switch D the motor circuit will be closed from the #POSlt-lVB lTlfllIl 2 by way of'contacts 10 and 12,,coriductor26, armature brush 27, arma- 'bure 25','-hr1ish '24-,contacts13, 11, conductor 12:1,

lfi'gfand. resistances. 62,

n'wtive'lead 3. .It-will he 0 served that the current isnowsent through the armature in'a reversed-direction to that when the reversiiigswitch U is closed.

- T lie shunt field being" excited and the brake apparatus being released from the hoisting unit controlled by the brake magnet 122, the load controlled by the latter is permitted to descend. At this time the closing of the switches 94 and 95 by the magnets" 82 and 83, respectively, has no further effect. When the reversing switch D is operated a circuit is closed also from the positive main" 2 through conductors 163, 192, contacts 37, 38 and bridge piece 35, conductor 400, electro-magnets 41, 42 a'nd'43, conductors 28,129, contacts 13, 11, conductor 164, and resistances 62, 63, 64, to the negative lead 3. The

Q magnets 41, 42, 43'are. therefore energized by being placed in a circuit across the armature and-will operate to close their switches.

' the plunger 65 being first lifted to bring the lifted to bring the plate 16 plate 44 1nto engagement with the contacts 47, the plu ger 66 then being lifted to bring the plate 4:) intojengagement with the contacts 48, and finally-the plunger 67 being into engagement with the contacts 49. The electrical connection of the contacts 47 places the resistance 50 in parallel with the'motor armature in the circuit from brush 24 through contacts 13-, 11, conductors 164,158, contacts 47 and plate 44, resistance 50, a portion of the nega-' tive lead 2, contacts 10, 12, conductor 26 to theother brush 2?. .This parallel circuit thus formed is of such low resistance that the current received by the armaturewill be comparatively small and therefore the motor will operate at slow speed. It, should be also noted that the resistances 62, 63 and 64 are in series with the motor armature, Which effects a still further reduction in speed of the motor. The latter resistances are always in series with the motor when the latter is lowering its load. The potential across the motor armature brushes, however, is at this time sufficient to effect theenergization of the magnet 33 and cause the latter to lift its plunger 34 and the plates 35, 36 and 37 connected thereto. A circuit for the magnet 41is opened at the contact- 38,

but another circuit for this magnet is still closed by the switch 100 through thecon ductor 155 at the contact segmentf1 06. However, as soon as the rheostat arm of switch 100 is moved out of engagemcntfwith.

the segmental strip 106, themagnet41 has its circuit opened. and the plunger ,wvill therefore drop. The resistances 5Q, 51 will then be placed in series with eachb'ther and in parallel with the armature. More current 'will then flow through the armature, owing to the increased resistance of the} parallel circuit. and consequently the motor will be accelerated. The magnets 42 and 43 still receive current at this time from the positivelead 2'through conductors 139, 138, segment 104 of the switch. 100, arm 102 contact strip 107, resistance 97, switch/94, conductor 159, magnets 42 and, 43, conductors 28, 25), contacts 13, 11, conductor'164, and resistances 6 2, 63, 64, to the negative lead 3. The, reslstance 97 is for the purpose of taking the place of the magnet 41 and-maintaining the current ,in the magnet 42 and 43 substantially the same as before.

\Vhen the rheost-at arm 102 is moved onto v the segment 108 the magnet 42 is open-circuited at the strip 107 and themagnet43 is alone excited by current passing through a circuit including the resistance 98 and the switch'95, the current in this circuit remaining substantially the same as before, owing to the resistance 98 being equal to the sum of the resistances of both magnets 41 and 42.

the magnet 42the resistance 52 is added to the resistances 50 and 51 in the circuit parallel to the armature. The motor will? therefore accelerate to a higher speed. A further movement of the arm 102 causes it to run Upon the opening of the circuit supplying off the strip 108 onto the strip 109. This a operationopensthe circuit of the magnet 43, causing the contacts 49 to become disconnected by the dropping of the plate 46. The parallel circuit to the motor armature placed in its'extreme position on the segment 110 inserts the resistance 101 in the shunt field circuit, thus brin ing the motor to its normal lowering speed It will thus .will then be opened.- The arm 102 when be seen that after themotor has been accelerated to full speed in lowering, t-he -resistances 62, 63 and 64 are in series with the motor armature, the resistances 50, 51

and 52 are entirely cutout and the resisttherefore drop, permitting the plate 35 to.

connect the contacts 37, 38 and the plate 36 .to connect the contacts 39, 40, and the plate to electrically disconnect the contacts 40,, The connection of the contacts 39,40 short-circuits the field resistance v1'01 ,by the conductors 163 and 130." The connection of.

the contacts 37and 38 places the magnets 41,42 and 43 across the motor, armature'.

These magnets will therefore receive current from the line and'will operate successively their switches to eflect the insertion of the resistance 50 in parallel to thearmature and causing the latter to be retarded, This retarding action is increased by the strengthening of the shunt field, due-to the cutt1ng oht of-the resistance 101. The hoisting machine will then lower the curtain at a reduced speed until when the curtaln almost a reaches its extreme limit of travel, the stop motion switch is opened by liftlng the memmotor forward as a generator one or more of the sections of resistance 50,51 and 52- may be inserted in a circuit "parallel to the" armature, thus obtaining areduction. in speed in proportion to the load. That is, ifthe load is. heavy and descending rapidly the momentum may be suflicie'nt to cause the motor, actiugas a generator, to energize all three of the electro-magnets 43, 42 and 41 action, since the resistance 50 alone is in series with themotor armature in a local circuit. If the momentum is not so reat then the magnets 43 and 42 alone'woul o erate and the retarding action would he '25 that due'to'; both the resistances 50 and 51.

When descending with a light load, although still'driving the motor as a generator, there will be less retarding action, and therefore onlyjhe magnet 43 will be energized and all the resistances 50, 51 and 52 kept in the electro-dynamic brake circuit.

The slow-down switch comprising the contacts 32 is operated in open position both when the curtainjapproac es its upper'limit of travel and when it approaches its lower limit of travel, and is operated: to such open position before the stop motion switch, comprising the member 118 for instance, is lifted. After the member 118 is lifted and so the brake mechanism applied to stop the multiple curtain hoisting unit, the member 31 is again permitted to connect the contacts 32, 32. This operation may be secured by any I well known stop motion apparatus, but I prefer to employ that illustrated in my copend'ing application Serial No. 282,234 here inbefore referred to. As indicated in Fig. 1' by the push button I switches and the brake'magnets, the controlling system is designed for a multiple hoisting apparatus" having six different units,. each controlled by an up and down manual switch, and up and down stop motion switch and by a brake 55 magnet. Furthermore, as before pointed out, the control of the hoisting units may be effected in two ways: First, the rheostat arm 102 is placed in a position corresponding to the desired speed and then a button selected for efiecting the operation of a corresponding unit. The motor then starts and carries the load up or down as described.

' Second-,the button is first pressed and the -1'heostat arm then moved from'its initial 6? position to a position corresponding to the to secure maximum electro-dynamic brake desired speed. The switches 72 and 73 are" safety switches and may beplaced in any, of the controllingcircuits desired for the purpose of stopping the hoisting units or the motor quickly in case of an emergency. 7o

that set forth 'inFig. .5 f my Coven-dingy 7 application Serial No..282,23-5 already g w ferred to. 25 esignates-the; motor armassi ture; 30, the shunt field winding; 280 andta 281, the reversing switches; 284, a bank of push buttons forselecting one of the brake magnets 286; .282, a manual controlling switch; 283, starting resistance; 268, the switch mechanism for controlling the start-.5.-

ing resistance; and 387, a. brake magnet for.

the electric motor itself. I

In the main motor circuit are .four 8861- on tions of the startingresistance 287, 288, 289,

i and 290 which are controlled by the-accelerating magnets 292, 293, 2,94 and 295. These controlling magnets are in turn controlled by the manual switch 282. The main circuit also contains the slow speed resist:

ances 296 and 297 which are controlled by. H the slow speed magnets 29 8- and 299, the

latterbeing connected to the manual switch 282. i 10 The reversing switches 280 and 281 are arranged to be operated by -electro-magnets compri'singsolenoi'ds 200, 201 and plungers. 202,203 movable therein. The plunger 202 is connectedto an insulating bar 204 which carries three'con'tacts 206, 207 and 208. The v latter contacts are arranged to" be moved into engagement with the contacts 212,213 and 214, respectively, when the solenoid 200 receives current. Ina similar manner the insulating bar 205 is connected to the, plunger 203 and carries the contacts 209, 210

. and 211, above which arethe fixed contacts Y 215, 216 and 217; The movablecontacts 206, 207 and 208- are connected to the binding posts 218, 219 and 220, respectively,and the movable contacts 209, 210 and 211 are connected to the binding posts 221, 222 and, 223. The binding-posts-219 and 222 are. connected respectively to the binding posts 1 221 and 225 oi"v the stop motion and brake 1 circuits hereinafter described. The binding post 218 is connected by the conductor; 226 to thebrush 227 of the motor' armature 25, the other brush 228 being connected by -the' conductor 229 to the resistances 290 and 296 f at the point 253. The binding posts 220 and 223 are connected together and to the resistance 287 and to the fixed contacts 234.

to .237, inclusive, by the-conductor 233. It

structed.

switch 282, it will be, seen that the same comprises a plurality of arc-shaped fixed contact strips consecutively arranged. These 7 contacts may be securedto a base of slate or other insulating material; The switch lever is here shown made of insulating material with contact strips or bridging pieces 334 and 335 secured to it. This lever may be of other material, however, and the bridging pieces separated electrically from it by means of insulation, or otherwise con- In order to start the motor the lever 241 moved to the right or left, depending upon the direction inwhich the motor is to run. Normalliy, that is, when the lever 241 is in, centra --'positio n. as shown, the pieces 334 and 335Qbridge respectively the strips 336, 337 and The strip 339 is electrically isolated. \Vhen the lever 241 is'moved to the right the conductor 335 will engage the strip 343. This \will result in closing the following circuit: from the positive main by way of conductor 244 to and through the solenoid 201, conductor 245, strip343, bridging contact 335, circular contact strip 340, conductors 246, 247 and-248 to-the negative main.

The closing of the circuit just traced effects the closing of the reversing switch 281 which establishes a circuit through the motor armature as indicated by the heavy lines which maybe traced as follows: from the positive lead 244 to and. through the contacts 215, 209, conductors 226, 249, brush 227, motor armature 25, brush 228, conductor 229, resistances 290, 289, 288 and 287,

CQIlClUCtO1"233, contacts 211, 217, and con-' ductor 248- to the negative main. There is also: established a circuit in shunt to the armature from conductor 226 by conductor 250 to vcontactstrip 337, bridging contact 334, strip 336, conductor 251, magnet- 298, conductor 252, to the point 253 where the conductor 229 from the brush 228 joins the resistances 296' and 290. The encrgization of the slow'spccd magnet .298 will cause the movable contact 254 to engage the fixed con-, tact 231 and insert the resistance 296 in parallel with the armature through the conductors 229, 239 and 249. The circuit of the shunt field winding-30 is also established and may betraccd from the binding post 219 througl the conductor-a255, 256, 257, 247 and 248 't0 the negative main. The motor will now start with thcstarting resistance 283 in series with the armature and the resistance 296 in parallel therewith, this being thecon'dition of slowest speed.

the switch lever 241 now be moved a little farther toward the right that the bridgthe strips 339 and 340.

resistance 268, the magnet 293, magnet ing'member 334 shall engage the strip 338. The space-between the strips 336 and 338 is' preferably a little less than the width of the bridging member 334 so that the latter will engage the strip338 before it leaves the strip 336. As soon as the member 334-en gages the strip 338 current may fiowthrough the conductor 250, strip 337, member 334,

strip 338, conductor 258 to the" other slow speed. magnet 299, and by way of-the conductor 252 to the point 253. It will thus be seen that the magnet 298 is-first connected across the armature and then also the mag will be placed in series with each other ina circuit parallel to-the motor armature. The resistance parallel to them-mature is therefore increased and the speed of the motor accelerated somewhat. A further movement of the lever 241 to' the right onto contact strip 259 will cause current to flow 1 by way of conductor 263 through the resistance 264 and, the accelerating magnet 292, conductors 265, 252 to the' point 253.

The movable contact 266 willbe drawn up against the fixed contact 234 and thus short circuit the resistance section 287. Thencxt step occurs when the member 334 leaves the strip 338, whereupon the magnet 299 will be dcencrgized and the resistance sections 296, 297 removed from the parallel circuit.

The resistances 288, 289 and 290 are now in series with the motor armature, the motor running at an increased-speed. \Vhen the member 334 is moved onto contact 360 current will flow through the conductor 267,

conductors 265,252 to the point 253. It

will be noticed that althougl i the resistance 264 is cut out by this last operation the magnet 292 ren1ains in circu t. The value of the resistance 268 is less than that ot the resistance '264 an amount approximately equal to the resistance of thesolenoid of the magnet 293 so that the current shall be I about ,the same as bcforc.- \Vhcn the, magnet 293 is cnm'gized'thc contacts 235, 271 will be connected and'both the resistances 287 and288short-oircuited. This will still further increase the speed ofthe motor. In

and 290 are short-circnitcd by a further movement of lever 241 to bring the motor up to full speed. i v

It should be noted that the resistances 264, 268 a'nd270 are so proportioned with respect to the resistances 'of the solenoids of the magnets 292, 293, 294 and 295 that the com-' a similar manncr also the resistances 289 bin'ed resistance of the solenoids and theres v between the resistances to the combined resistances 'sistafires-that are in circuitat any time remain substantially-the same. That is, when only the magnet 292 is energized the resistance 254 is sutlicientto cut down the current to'what it will be when all the magnets are connected in seriesand all of them energized.

The difference-between the "resistances 264 and 268 is equal to the resistance of the solenoid of the magnet 29 3, and the difference 264 and 270 is equal of the solenoids of the magnets 293 and 294. 'Also the coinbined-resistances of the solenoids of the magnets 293, 294 and 295 is equal to the resistance 264. It should be also noted that with this arrangement of accelerating magnets, I am enabled to bring the motor up to any speed desired, dependent upon the position of the manual controlling switch. more, by returning the switch lever 241 I am enabled to reduce the speed of the motor to I any point corresponding to the position. of

i the switch lever.

In other words, the speed of the motor is always dependent upon the position of the switch lever 241 and may be increased or decreased at will. Preferably the starting resistance should be so proportioned as to give a wide range of speed for the motor. The number of sections of the starting resistance may be varied as desired,

the greater the number the greater the re finement of speed control.

Referring-to the bank of push buttons 284,

it will be noticed that each is provided with 'two electro-magnets, operate the button in the same direction; The series of electro-magnets 277 are {con'- with each other and are jnormally energized by current passing from the, positive main to and through the contact 216,]

each ofaw'hich tends to nected in series conductor 274, switch 275, conductor 276, electro-magnets 277, conductors 257 and 247 to the negative mam. Current is always" passing through this circuit when the main line switch 1 is-closed,-but the energization of the electro-magnets 277, is insuiiicient to close the series of switches 27.8. When, how

ever, a push button is pressed in to close, onethe action of a of the switches 278 against spring 383, the corresponding electro-magnet 277 will have sufficient strength to new it closed. So long as the mahual cont-gplling {switch282 remains in normal position and 's:

neitherreversing switch is closed, the-switch 275 will remain closed and the operation of one or more of the push buttons284 will have no operative effect except to set them in readiness to cause the brake magnet tobe energized, and thus automatically connect a hoisting apparatus anda rotating friction disk. series'of solenoids being a holding or retain pressedin after haying once been operated Further. f

"right to operate the The-shunt field circuit being closed the" That is,-the circuit through the upper to hold a I button assess so that any particular group ohhiiistihg'devices may ated together.

automatic limit switches the buttons will he released to return to.theirnormatpositions,

be selected beforehand to be oper- Upon the;operation of the.

provided the switch 27 5 is in open position i at such time.

Each of the up limit switch 381, the solenoids of the brake magnets 286 isprovided' with a down limit switch 380 and an S magnets 28fibeing'connected to them at in-fv termediate points. All of the down limit switches are connected to' the binding posts- 224 and the up limit switches to the binding posts 225.

It will be apparent that when one limit switch is. opened the other i still remains closed. ing switch isclosed the other is in opened position,

though one of the limit switches is open.

The down limit switches cannot convey current when the movement of the load is upward; the samecondition holds with 're-- gard to the up limit switches whose circuits are broken when the down reversing switch is. closed.

Also when one revers and the latter maybe operated al- 'As-soon'a's the current begins to flow in 'the shunt field circuit the magnet 382 therein "will openthe'switch 275-and this has the effect of deenergir .ing electro m'agnets 277 of the push button appathe upper. series of ratus284. The push buttons that had been operated would then'fly out of their normal positions by reason OfiillQ springs 383, unless-held in by one of .t-he'electroqnagnets 384 in one of the brake magnet circuits.

Assuming that all the push buttons have been operated 277;"let th'e'switch lever 241 be moved toiiithe up reversing switch.

magnet 382 will be energized to open the switch'275 to breakthe circuit of the magn'etsf27 7'.' But before this can take place current flows from the positive main through the contacts 216, 210, binding posts cuits 3fi5, v the brake magnets nets 384, switches 2.78 to the conductors 24.7, and thence fithe 286, circuits 386, electro-ma erg'ized' to hold. the

pressed in positionsand consequently maintain the selected brake magnets energized. If only'one orless than all of the push buttons have been actuated, those which have not been operated will remain inoperative, by reason of the switches controlled thereby remainingin opened position,

ceiving current.

The motor havingjstarteghits speed may I 180 be a l led as desired and theb ake magnets I the'l'owr elec' tro-magnets-t384 thereof therefore not rep and are held in circuit-closing'. position by the upper series of magnets corresponding to the operated push buttons tion the motor will of course be brou ht to rest, a brake being applied antomatica ly to the motor shaft, which brake may be released by means of a brake magnet 38? whenever one of the reversing switches is closed. lVhen the switch 282 is in its normal position the, shunt field circuit is interrupted at the reversing switches and the magnet 382 therefore again permits the switch 275 to be brought to closed position. The circuit through the holding electromagnets 277 is therefore again established.

Obviously those skilled in the art may make varlous changes in details and arrangement of parts without departing from the spirit and scope of my invention asdefined by the appended claims, and I desire therefore not to be'limited to. the prec se construction and connections herein disclosed. 7

.What I claim and desirefto have protectedby Letters Patent of the United States- 1. The combination with an electric motor, of starting and stop ing apparatus therefor, a switch, means dependent upon the position of said switch for varying the speed of said motor without stopping the same, a multiple of brake elcctro-maguets, and means for selecting one or more of said electro-magnets.

2. The combination with an electric motor, of sectional starting. resistance, manual electric switch, 1neans controlled by said switch for varying said resistance to effect a variation inthe speed of said motor, the speed of the 'motor at any time corresponding to predetermined positions of said switcl1,-a multiple of brake Imagnets, and a selective system for the latter.

3. The combinationwlth an electric motor, of sectional starting resistance in series therewith, additional resistancein :1 normally open circuit and parallel with the armature, and ineans comprising a manual switch for controlling said resistances to vary the speed of the motor at will, whether the motor acting as such is rotating in onedirection or the other.

4. The combination with an" electric motor, of resistance in a normally open circuit and parallel to the motor armature, starting resistancein series with the armature, separate electro-magneticmechanism for controlling the respective resistances, and a manual switch for effecting the operation of said mechanism to vary thespeed of the niotor dependent upon the osit'ionof said switch irrespective of the direction of rotation of the motorarmature.

In multiple curtain hoisting apparatus,

the combination with an electrlc motor, of.

starting and stopping apparatus therefor,

speed controlling mechanism, a. series of eleetro-magnet-ic push button switches, a corresponding series of devices to be controlled by said switches, and means for retaining selected switchesin closed position.

I 6. In motor controlling apparatus, the combination. with an electric motor, of re vex-sing switches therefor, of sectional starting resistance, a series of switches for controlling said resistance, a series'of electro-.

magnets for operating said switches, a mannal switch for controlling the operation of said elcctromagnets and etl'ectmg a variation of speed of the electric motor,-a relay for controlling the circuit of said electrom'agnetspand a switch for causing said relay to open the magnet circuit and re-insert the starting resistance to slow down the motor.

7, in -motor controlling apparatus, the combination with an electric motor, of reversing switches therefor, clectro-magncts for operating said reversing switches, relays tor controlling said electroanagnets, accel crating apparatus, addltional relays, a manual switch co-acti-ng with said additional relays to control said accelerating apparatus,

and additionalswitches for controllingall of said relays. i v

'8. ln motor controlling apparatus, the

combination with an electric motor, of-re- 1 xersing switchcstlierefor, starting resistance,- clectro-magnetie switches and controlling means for -varying said resistance to ac' cclerate the motor when operating in one direction, additional resistanceraml another series of electro-magnetic switches operated to insert said additional resistance in parallel to the motor armature when the motor is being rotated in the oppos te (l1-- rcction.

9. In \motor controlling apparatus, thecomlnnation with an electric motor, of starting' and accelerating apparatus therefor, means for controlling the speed of the'motor in a predetermineddirection, and a relay dependent upon armature potential for controlling both the accelerating apparatus and the said speed varying means.

4 10. In motor controlling apparatus, the

combination with an electric motor, of startin r app aratnstlgerefor, electro-magnetic ac ce crating devices, a, resistance and a switch for inserting said resistance in the shunt field circuit of the nmi' r toincrease the across the'motor armature, and switches operated 'by said magnet to render the aecel v erating devices inoperative and to cut out said field resistance to automatically reduce the speed of the motor 11. In. motor controlling apparatus, the combination with an electric motor, of accelerating apparatus therefor, a resistance, a means for inserting said resistance in the shunt field circuit to increase the-speedof the motor, a magnet connected across the v armature, and a switch for short-circuiting held open by said magnet.

' 12. In motor controlling apparatus, the.

said resistance when '.closed but normally combination with a motor, of controlling speed thereof, an eleoti'o'magnet connected means therefor, electro-dynamic appliances entirely electrical for retarding the, operation of said motor, a series of electro-magnets for operating said appliances, a manual motor armature, and a relay dependent ii pon armature potential for controlling the op V. H. Bik ni, A. M. ZABRISKIE.

erativeness of'said magnets and appliances.

name to this specification in the presence of switch for connecting one or more of said magnets in series with each other-across the 

